Abstract
Selection of sustainable wastewater treatment scenarios under different local contexts is a complex process because of the inherent trade-offs among socio-economic, environmental and technical as well as functional factors. In order to fulfill conflicting yet complementary objectives, an integrated and systematic approach called the "multi-criteria analysis" (MCA) using a multi-dimensional set of criteria and life cycle assessment (LCA) tools as effective decision support mechanisms for integrated evaluation and selection of sustainable small-town wastewater treatment systems has been developed. Application of this approach was illustrated through a case study of the small Vietnamese town Toan Thang, with an estimated total population of 10,000 people. A short-list of 3 selected scenarios and a multi-dimensional set of criteria facilitated a complex decision-making process. The qualitative analysis results presented in the spider-web diagram as well as the quantitative analysis results from various impact assessments have indicated clearly that the use of waste stabilization ponds is ranked as the first priority and seems to be the most promising and sustainable choice for the town under consideration. The results obtained from this study can be used as a scientific basis and could be valuable inputs for stakeholders' consultation and preference assessment in searching for the most suitable solution under their local context.
